U.S. patent application number 13/727990 was filed with the patent office on 2013-07-18 for ring rolling mill and ring rolling method.
This patent application is currently assigned to Mitsubishi Materials Corporation. The applicant listed for this patent is Mitsubishi Materials Corporation. Invention is credited to Shimpei HIROSE, Yuji Ishiwari, Hiroaki Kikuchi, Hideo Takizawa.
Application Number | 20130180302 13/727990 |
Document ID | / |
Family ID | 38563442 |
Filed Date | 2013-07-18 |
United States Patent
Application |
20130180302 |
Kind Code |
A1 |
HIROSE; Shimpei ; et
al. |
July 18, 2013 |
RING ROLLING MILL AND RING ROLLING METHOD
Abstract
This ring rolling mill includes a main roll and a mandrel that
are brought close to or separated from each other, and roll a
peripheral portion of a ring-shaped body in a radial direction of
the ring-shaped body while the ring-shaped body is rotated along
its peripheral direction in a state where the peripheral portion of
the ring-shaped body is pinched in the radial direction between an
outer peripheral surface of the main roll, and an outer peripheral
surface of the mandrel. This ring rolling mill further includes a
mechanism which inclines and supports the mandrel with respect to
the rotation axis of the main roll such that the gap between the
outer peripheral surface of the mandrel and the outer peripheral
surface of the main roll differs on one side and on the other side
as seen in a direction along the rotation axis of the main
roll.
Inventors: |
HIROSE; Shimpei;
(Kagawa-gun, JP) ; Ishiwari; Yuji; (Okegawa-shi,
JP) ; Kikuchi; Hiroaki; (Okegawa-shi, JP) ;
Takizawa; Hideo; (Saitama-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mitsubishi Materials Corporation; |
Tokyo |
|
JP |
|
|
Assignee: |
Mitsubishi Materials
Corporation
Tokyo
JP
|
Family ID: |
38563442 |
Appl. No.: |
13/727990 |
Filed: |
December 27, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12294533 |
Sep 25, 2008 |
8365564 |
|
|
PCT/JP2007/056677 |
Mar 28, 2007 |
|
|
|
13727990 |
|
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Current U.S.
Class: |
72/101 |
Current CPC
Class: |
B21H 1/06 20130101; B21B
17/02 20130101; B21B 5/00 20130101 |
Class at
Publication: |
72/101 |
International
Class: |
B21B 17/02 20060101
B21B017/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 29, 2006 |
JP |
2006-089750 |
Claims
1-6. (canceled)
7. A ring rolling mill comprising a main roll and a mandrel
provided so as to be capable of being brought close to or separated
from each other, the ring rolling mill rolling a peripheral portion
of a ring-shaped body in a radial direction of the ring-shaped body
while the ring-shaped body is rotated along its peripheral
direction in a state where the peripheral portion of the
ring-shaped body is pinched in the radial direction between an
outer peripheral surface of the main roll which is rotationally
driven, and an outer peripheral surface of the mandrel which is
rotatable, wherein the ring rolling mill further comprises a main
roll inclining/supporting mechanism which inclines and supports the
main roll with respect to the axis of rotation of the mandrel such
that a gap between the outer peripheral surface of the mandrel and
the outer peripheral surface of the main roll differs on one side
and on the other side as seen in a direction along the axis of
rotation of the mandrel.
8. The ring rolling mill according to claim 7, wherein the main
roll inclining/supporting mechanism includes: a first main roll
supporting portion which rotatably supports one end of the main
roll in place; a second main roll supporting portion which
rotatably supports the other end of the main roll; and a first main
roll driving section which brings or separates the second main roll
supporting portion close to or from the mandrel.
9. The ring rolling mill according to claim 7, wherein the main
roll inclining/supporting mechanism includes: a first main roll
supporting portion which rotatably supports one end of the main
roll in place; a second main roll supporting portion which
rotatably supports the other end of the main roll; and a second
main roll driving portion which independently brings or separates
both the first main roll supporting portion and the second main
roll supporting portion close to or from the mandrel.
10-11. (canceled)
12. A ring rolling method of rolling a peripheral portion of a
ring-shaped body in its radial direction while the ring-shaped body
is rotated along its peripheral direction in a state where the
peripheral portion of the ring-shaped body is pinched between a
main roll and a mandrel provided so as to be capable of being
brought close to or separated from each other, wherein the ring
rolling method comprises inclining and supporting the main roll
with respect to the axis of rotation of the mandrel such that a gap
between an outer peripheral surface of the mandrel and an outer
peripheral surface of the main roll differs on one side and on the
other side as seen in a direction along the axis of rotation of the
main roll.
13. The ring rolling method according to claim 12, comprising:
rolling the peripheral portion of the ring-shaped body while
inclining the main roll such that the gap become smaller on the one
side than on the other side; and rolling the peripheral portion of
the ring-shaped body while inclining the main roll such that the
gap become smaller on the other side than on the one side.
Description
CROSS REFERENCE TO PRIOR RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. patent application
Ser. No. 12/294,533, filed Sep. 25, 2008, which is a U.S. national
phase application under 35 U.S.C. .sctn.371 of International Patent
Application No. PCT/JP2007/056677 filed Mar. 28, 2007, and claims
the benefit of Japanese Patent Application No. 2006-089750 filed on
Mar. 29, 2006, both of which are incorporated by reference herein.
The International Application was published on Oct. 11, 2007 as
International Publication No. WO 2007/114174 A1 under PCT Article
21(2).
FIELD OF THE INVENTION
[0002] The present invention relates to a ring rolling mill and a
ring rolling method which roll a peripheral portion of a
ring-shaped body in a radial direction.
BACKGROUND OF THE INVENTION
[0003] For example, a conventional ring rolling mill disclosed in
Patent Document 1, etc. rolls a peripheral portion of a ring-shaped
body in a radial direction while the ring-shaped body is rotated in
its peripheral direction, with the peripheral portion pinched in
the radial direction between an outer peripheral surface of a main
roll which is rotationally driven, and an outer peripheral surface
of a mandrel which is rotatable. Also, in the conventional ring
rolling mill, the peripheral portion of the ring-shaped body is
rolled in the radial direction by the outer peripheral surfaces of
the main roll and the mandrel by relatively bringing or separating
the main roll and the mandrel close to or from each other in a
state where their axes of rotation are kept substantially parallel
to each other.
[0004] However, in the conventional ring rolling mill, the main
roll and the mandrel are brought close to or separated from each
other in a state where their axes of rotation are kept
substantially parallel to each other. Thus, the pressing forces
applied on the peripheral portion of the ring-shaped body by the
main roll and the mandrel could be made different in every
peripheral position on the peripheral portion, but could not be
made different in every position in the thickness direction. That
is, the pressing forces could not be made different locally in the
peripheral portion of the ring-shaped body. [0005] Patent Document
1: Japanese Patent Publication No. 2859446
SUMMARY OF THE INVENTION
[0006] The invention has been made in view of the above
circumstances. The object of the invention is to provide a ring
rolling mill and a ring rolling method capable of making pressing
forces applied on a peripheral portion of a ring-shaped body by a
main roll and a mandrel made different locally in the peripheral
portion of the ring-shaped body.
[0007] In order to solve the above problems, the invention has
adopted the followings.
[0008] (1) A ring rolling mill including a main roll and a mandrel
provided so as to be capable of being brought close to or separated
from each other, and rolling a peripheral portion of a ring-shaped
body in a radial direction of the ring-shaped body while the
ring-shaped body is rotated along its peripheral direction in a
state where the peripheral portion of the ring-shaped body is
pinched in the radial direction between an outer peripheral surface
of the main roll which is rotationally driven, and an outer
peripheral surface of the mandrel which is rotatable, the ring
rolling mill further including a mandrel inclining/supporting
mechanism which inclines and supports the mandrel with respect to
the axis of rotation of the main roll such that the gap between the
outer peripheral surface of the mandrel and the outer peripheral
surface of the main roll differs on one side and on the other side
as seen in a direction along the axis of rotation of the main
roll.
[0009] According to the ring rolling mill of the above (1), the
mandrel is inclinedly supported by the mandrel inclining/supporting
mechanism. Thus, the pressing forces applied on the peripheral
portion of the ring-shaped body by the main roll and the mandrel
can be made different not only in the peripheral direction of the
peripheral portion, but also in the thickness direction. As a
result, the pressing forces can be made different in every portion
rolled in the peripheral portion of the ring-shaped body, that is,
locally. For example, while the ring-shaped body makes one rotation
in the process during which the ring-shaped body is rolled while
being rotated in its peripheral direction, the inclination angle of
the mandrel can be made different two or more times, or the mandrel
can be kept at the same inclination angle while the ring-shaped
body makes one rotation.
[0010] (2) In the ring rolling mill of the above (1), the mandrel
inclining/supporting mechanism may include a supporting frame which
supports upper and lower ends of the mandrel; and a frame tilting
mechanism which tilts the supporting frame.
[0011] (3) In the ring rolling mill of the above (1), the mandrel
inclining/supporting mechanism may include a first mandrel
supporting portion which rotatably supports one end of the mandrel
in place; a second mandrel supporting portion which rotatably
supports the other end of the mandrel; and a first mandrel driving
section which brings or separates the second mandrel supporting
portion close to or from the main roll.
[0012] (4) In the ring rolling mill of the above (3), the first
mandrel driving section may include an eccentric shaft fixed in
place; a first connecting frame which connects the eccentric shaft
and the first mandrel supporting portion; and a rotation driving
portion which rotates the eccentric shaft.
[0013] (5) In the ring rolling mill of the above (3), the first
mandrel driving section may include a base portion fixed in place;
a second connecting frame which connects the base portion and the
first mandrel supporting portion; and a sliding driving portion
which moves the second connecting frame relative to the base
portion.
[0014] (6) In the ring rolling mill of the above (1), the mandrel
inclining/supporting mechanism may include a third mandrel
supporting portion which rotatably supports one end of the mandrel;
a fourth mandrel supporting portion which rotatably supports the
other end of the mandrel; and a second mandrel driving portion
which independently brings or separates both the third mandrel
supporting portion and the fourth mandrel supporting portion close
to or from the main roll.
[0015] (7) A ring rolling mill including a main roll and a mandrel
provided so as to be capable of being brought close to or separated
from each other, and rolling a peripheral portion of a ring-shaped
body in a radial direction of the ring-shaped body while the
ring-shaped body is rotated along its peripheral direction in a
state where the peripheral portion of the ring-shaped body is
pinched in the radial direction between an outer peripheral surface
of the main roll which is rotationally driven, and an outer
peripheral surface of the mandrel which is rotatable, the ring
rolling mill further including a main roll inclining/supporting
mechanism which inclines and supports the main roll with respect to
the axis of rotation of the mandrel such that the gap between the
outer peripheral surface of the mandrel and the outer peripheral
surface of the main roll differs on one side and on the other side
as seen in a direction along the axis of rotation of the
mandrel.
[0016] According to the ring rolling mill of the above (7), the
main roll is inclinedly supported by the main roll
inclining/supporting mechanism. Thus, the pressing forces applied
on the peripheral portion of the ring-shaped body by the main roll
and the mandrel can be made different not only in the peripheral
direction of the peripheral portion, but also in the thickness
direction. As a result, the pressing forces can be made different
in every portion rolled in the peripheral portion of the
ring-shaped body, that is, locally. For example, while the
ring-shaped body makes one rotation in the process during which the
ring-shaped body is rolled while being rotated in its peripheral
direction, the inclination angle of the main roll can be made
different two or more times, or the main roll can be kept at the
same inclination angle while the ring-shaped body makes one
rotation.
[0017] (8) In the ring rolling mill of the above (7), the main roll
inclining/supporting mechanism may include a first main roll
supporting portion which rotatably supports one end of the main
roll in place; a second main roll supporting portion which
rotatably supports the other end of the main roll; and a first main
roll driving section which brings or separates the second main roll
supporting portion close to or from the mandrel.
[0018] (9) In the ring rolling mill of the above (7), the main roll
inclining/supporting mechanism may include a first main roll
supporting portion which rotatably supports one end of the main
roll in place; a second main roll supporting portion which
rotatably supports the other end of the main roll; and a second
main roll driving portion which independently brings or separates
both the first main roll supporting portion and the second main
roll supporting portion close to or from the mandrel.
[0019] (10) A ring rolling method of rolling a peripheral portion
of a ring-shaped body in its radial direction while the ring-shaped
body is rotated along its peripheral direction in a state where the
peripheral portion of the ring-shaped body is pinched between a
main roll and a mandrel provided so as to be capable of being
brought close to or separated from each other, the ring rolling
method including inclining and supporting the mandrel with respect
to the axis of rotation of the main roll such that the gap between
an outer peripheral surface of the mandrel and an outer peripheral
surface of the main roll differs on one side and on the other side
as seen in a direction along the axis of rotation of the main
roll.
[0020] According to the ring rolling mill of the above (10), the
mandrel is inclined and supported. Thus, the pressing forces
applied on the peripheral portion of the ring-shaped body by the
main roll and the mandrel can be made different not only in the
peripheral direction of the peripheral portion, but also in the
thickness direction. As a result, the pressing forces can be made
different in every portion rolled in the peripheral portion of the
ring-shaped body, that is, locally. For example, while the
ring-shaped body makes one rotation in the process during which the
ring-shaped body is rolled while being rotated in its peripheral
direction, the inclination angle of the mandrel can be made
different two or more times, or the mandrel can be kept at the same
inclination angle while the ring-shaped body makes one
rotation.
[0021] (11) The ring rolling method of the above (10) may include
inclining the mandrel such that the gap become smaller on the one
side than on the other side, thereby rolling the peripheral portion
of the ring-shaped body; and inclining the mandrel such that the
gap become smaller on the other side than on the one side, thereby
rolling the peripheral portion of the ring-shaped body.
[0022] In this case, when the whole area of the peripheral portion
of the ring-shaped body in its thickness direction is rolled over
its whole periphery, this peripheral portion is rolled over its
whole periphery in twice half and half in its thickness direction.
Thereby, the contact area between the peripheral portion of the
ring-shaped body and the mandrel at every rolling is made small, so
that the compressive stress applied on the peripheral portion of
the ring-shaped body can be increased.
[0023] Accordingly, the amount of processing for rolling the
peripheral portion of the ring-shaped body in the radial direction
can be made large in a state where the driving force which brings
the main roll and the mandrel close to each other are kept equal to
that of an existing model. As a result, compactness of a ring
rolling mill used for this ring rolling method can be achieved.
Moreover, since such rolling can be performed while the ring-shaped
body is rotated in its peripheral direction without being removed
from the ring rolling mill, the efficiency of processing can also
be made high.
[0024] In addition, if rolling of the peripheral portion of a
ring-shaped body in every position in its thickness directional is
carried out, for example, using dies, it is necessary to take out
the ring-shaped body from a cavity and heat this whenever this
processing position changes. Thus, there is a possibility that a
significant drop in manufacture efficiency may be caused.
[0025] (12) A ring rolling method of rolling a peripheral portion
of a ring-shaped body in its radial direction while the ring-shaped
body is rotated along its peripheral direction in a state where the
peripheral portion of the ring-shaped body is pinched between a
main roll and a mandrel provided so as to be capable of being
brought close to or separated from each other, the ring rolling
method including inclining and supporting the main roll with
respect to the axis of rotation of the mandrel such that the gap
between an outer peripheral surface of the mandrel and an outer
peripheral surface of the main roll differs on one side and on the
other side as seen in a direction along the axis of rotation of the
main roll.
[0026] According to the ring rolling mill of the above (12), the
main roll is inclined and supported. Thus, the pressing forces
applied on the peripheral portion of the ring-shaped body by the
main roll and the mandrel can be made different not only in the
peripheral direction of the peripheral portion, but in the
thickness direction. As a result, the pressing forces can be made
different in every portion rolled in the peripheral portion of the
ring-shaped body, that is, locally. For example, while the
ring-shaped body makes one rotation in the process during which the
ring-shaped body is rolled while being rotated in its peripheral
direction, the inclination angle of the main roll can be made
different two or more times, or the main roll can be kept at the
same inclination angle while the ring-shaped body makes one
rotation.
[0027] (13) The ring rolling method of the above (12) may include
inclining the main roll such that the gap become smaller on the one
side than on the other side, thereby rolling the peripheral portion
of the ring-shaped body; and inclining the main roll such that the
gap become smaller on the other side than on the one side, thereby
rolling the peripheral portion of the ring-shaped body.
[0028] In this case, the same operational effects as those of the
ring rolling method of the above (11) can be obtained.
ADVANTAGES OF THE INVENTION
[0029] According to the present invention, the pressing forces
applied on the peripheral portion of the ring-shaped body by the
main roll and the mandrel can be made different locally in the
peripheral portion of the ring-shaped body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a side view showing a first embodiment of a ring
rolling mill of the present invention, with a portion shown in
section.
[0031] FIG. 2 is a perspective view showing a lower frame body and
a second fitting projection when the axis of rotation of a main
roll and the axis of rotation of a mandrel are parallel to each
other in the ring rolling mill.
[0032] FIG. 3 is a perspective view showing the lower frame body
and a first fitting projection when the axis of rotation of the
main roll and the axis of rotation of the mandrel are parallel to
each other in the ring rolling mill.
[0033] FIG. 4 is a sectional view of the lower frame body and the
first fitting projection shown in FIG. 3.
[0034] FIG. 5 is a sectional view of the lower frame body and the
second fitting projection shown in FIG. 2.
[0035] FIG. 6 is a side view when the axis of rotation of the
mandrel is inclined such that a gap between a vertical upper
portion of an outer peripheral surface of the mandrel, and an outer
peripheral surface of the main roll becomes smaller than a gap
between a vertical lower portion of the outer peripheral surface of
the mandrel, and the outer peripheral surface of the main roll, in
the ring rolling mill, with a portion shown in section.
[0036] FIG. 7 is a perspective view showing the lower frame body
and the second fitting projection of this ring rolling mill in the
state of FIG. 6.
[0037] FIG. 8 is a view when the axis of rotation of the mandrel is
inclined such that a gap between the vertical upper portion of the
outer peripheral surface of the mandrel, and the outer peripheral
surface of the main roll becomes larger than a gap between the
vertical lower portion of the outer peripheral surface of the
mandrel, and the outer peripheral surface of the main roll, in the
ring rolling mill, and is a perspective view of the lower frame
body and the second fitting projection.
[0038] FIG. 9 is a side view in the above state of the ring rolling
mill, with a portion shown in section.
[0039] FIG. 10A is a sectional view for explaining the step of
correcting a taper during rolling of the ring-shaped body.
[0040] FIG. 10B is a sectional view for explaining continuation of
the correcting step.
[0041] FIG. 10C is a sectional view for explaining continuation of
the correcting step.
[0042] FIG. 11A is a side view showing a second embodiment of the
ring rolling mill of the present invention.
[0043] FIG. 11B is a sectional view of an A portion of FIG.
11A.
[0044] FIG. 12 is a side view for explaining the operation of the
ring rolling mill.
[0045] FIG. 13 is a side view for explaining the operation of the
ring rolling mill.
[0046] FIG. 14 is a sectional view for explaining a supporting
mechanism of the mandrel in the ring rolling mill.
[0047] FIG. 15 is a B-B sectional view of FIG. 14 showing the
supporting mechanism.
[0048] FIG. 16 is a side view showing a third embodiment of the
ring rolling mill of the present invention.
[0049] FIG. 17 is a side view for explaining the operation of the
ring rolling mill.
[0050] FIG. 18 is a side view for explaining the operation of the
ring rolling mill.
[0051] FIG. 19 is a side view showing a fourth embodiment of the
ring rolling mill of the present invention.
[0052] FIG. 20 is a side view for explaining the operation of the
ring rolling mill.
[0053] FIG. 21 is a side view for explaining the operation of the
ring rolling mill.
[0054] FIG. 22 is a side view showing a fifth embodiment of the
ring rolling mill of the invention.
[0055] FIG. 23 is a side view for explaining the operation of the
ring rolling mill.
[0056] FIG. 24 is a side view for explaining the operation of the
ring rolling mill.
DETAILED DESCRIPTION OF THE INVENTION
Best Mode for Carrying Out the Invention
[0057] Respective embodiments of a ring rolling mill and a ring
rolling method of the present invention will be described below,
referring to the drawings.
First Embodiment
[0058] A first embodiment of the present invention will first be
described below, referring to FIG. 1 to FIG. 10C. A ring rolling
mill 10 of this embodiment, as shown in FIG. 1, includes a main
roll 11 and a mandrel 21 which are provided so as to be capable of
being brought close to or separated from each other. With a
peripheral portion of a ring-shaped body W pinched in its radial
direction between an outer peripheral surface of the main roll 11
which is rotationally driven around its axis, and an outer
peripheral surface of the mandrel 21 which is rotatable around its
axis, the peripheral portion is rolled in the radial direction
while the ring-shaped body W is rotated in its peripheral
direction.
[0059] In addition, the ring-shaped body W is formed by
slab-forging melted ingot, and then forming a through hole in this
ingot.
[0060] In the position opposite the main roll 11 and the mandrel 21
with the axis of the ring-shaped body W therebetween, a pair of
axial rolls 41 which pinches the ring-shaped body W in its
thickness direction is provided so as to be capable of being
rotationally driven around their axes of rotation. The axial rolls
41 are supported so as to be capable of advancing and retreating
along the radial direction of the ring-shaped body W.
[0061] The main roll 11 is supported by a fixed frame 12 so as to
be capable of being rotationally driven around its axis of rotation
in a state where its axis of rotation runs along a' vertical
direction. The outer peripheral surface of the main roll 11
supports an outer peripheral surface of the ring-shaped body W.
[0062] The mandrel 21 is supported so as to be rotatable around its
axis of rotation with respect to a movable frame 22 in a state
where its axis of rotation is substantially parallel to the axis of
rotation of the main roll 11. The inner peripheral surface of the
ring-shaped body W presses the outer peripheral surface of the
mandrel 21 outward in its radial direction.
[0063] The movable frame 22 includes a pair of upper frames 23
which extend horizontally toward the main roll 11 from the mandrel
21, a pair of lower frames 24 which are provided vertically below
the upper frames 23 and extend substantially parallel to an
extension direction of the upper frames 23, and an intermediate
frame 25 which connects each upper frame 23 and each lower frame
24. The intermediate frame 25 connects the rear end of each upper
frame 23 and the rear end of each lower frame 24 opposite their
front ends on the side where the mandrel 21 is disposed.
[0064] Bridging frames (not shown) which connect the pair of upper
frames 23 and the pair of lower frames 24, respectively, are
disposed at the front end of each upper frame 23 and at the front
end of each lower frame 24, respectively. Both ends of the mandrel
21 in the direction of its axis of rotation are supported by these
bridging frames so as to be rotatable around the axis of the
mandrel.
[0065] Each upper frame 23 is supported so as to be rotatable in
the vertical direction about a pin 25a inserted through the
intermediate frame 25. A base end of an opening/closing cylinder 26
is attached to the intermediate frame 25. A distal end of a rod of
the cylinder 26 is attached to a lower surface of the upper frame
23. Thereby, when the opening/closing cylinder 26 is driven to
advance and retreat, each upper frame 23 rotates in the vertical
direction about the pin 25a along with the bridging frames and the
mandrel 21 which are provided at the front ends of the upper frames
23.
[0066] The intermediate frame 25 is provided with an
advance/retreat driving cylinder 27. Also, the distal end of the
rod of the advance/retreat driving cylinder 27 is connected with
the fixed frame 12 which supports the main roll 11. Consequently,
if the advance/retreat driving cylinder 27 is driven to advance and
retreat, the reaction force from the fixed frame 12 acts on the
intermediate frame 25, and the whole movable frame 22 including the
intermediate frame 25, the upper frame 23, the lower frame 24, and
each of the bridging frame moves horizontally along with the
mandrel 21.
[0067] The lower frames 24 are supported by a pair of rail portions
28, respectively, which extend substantially parallel to the
extension direction of the frames 24. Each lower frame 24 includes
a pair of lower frame bodies 29 which extend horizontally toward
the main roll 11 from the mandrel 21, and first and second fitting
projections 30 and 31 which are respectively provided at both
longitudinal ends of each of outer lateral surface 29c opposite the
inner lateral surfaces which face each other, among outer surfaces
of the lower frame bodies 29. That is, the front end of both the
longitudinal ends of the outer lateral surface 29c on the side
where the mandrel 21 is disposed is provided with the first fitting
projection 30, and the rear end opposite the front end is provided
with the second fitting projection 31.
[0068] As shown in FIGS. 4 and 5, as the first and second fitting
projections 30 and 31 are slidably fitted into grooves 28a,
respectively, which are formed in the inner lateral surfaces which
face each other in the pair of rail portions 28, the lower frames
24 are supported by the rail portions 28.
[0069] Further, as the pins 29a provided so as to protrude from
both the longitudinal ends on the outer lateral surface 29c of the
lower frame body 29 are fitted into holes, respectively, which are
formed in the first and second fitting projections 30 and 31,
respectively, the first and second fitting projections 30 and 31
are rotatably supported about the pins 29a.
[0070] The first fitting projection 30 is such that a portion into
which the pin 29a of the lower frame body 29 is fitted, and a
portion which is fitted into the groove 28a of the rail portion 28
are formed integrally.
[0071] As shown in FIGS. 2 and 5, the second fitting projection 31
includes an upper fitting projection 31a which is rotatably fitted
into the pin 29a of the lower frame body 29, and a lower fitting
projection 31b which is arranged below the upper fitting projection
31a, and is slidably fitted into the groove 28a of the rail portion
28.
[0072] An elevating cylinder 32 which can advance and retreat in
the vertical direction is provided inside the lower fitting
projection 31b. The upper fitting projection 31a and the lower
fitting projection 31b are connected together via a rod 32a of the
cylinder 32. When the rod 32a of the elevating cylinder 32 is
located in the intermediate position between an extended end and a
retracted end, that is, when a gap is formed between a lower
surface of the upper fitting projection 31a and an upper surface of
the lower fitting projection 31b, the extension direction of the
lower frame bodies 29 and the extension direction of the rail
portion 28 become parallel to each other, and the axis of rotation
of the main roll 11 and the axis of rotation of the mandrel 21
become parallel to each other.
[0073] If the rod 32a of the elevating cylinder 32 is retracted
from this parallel state, as shown in FIGS. 6 and 7, the lower
surface of the upper fitting projection 31a and the upper surface
of the lower fitting projection 31b contact each other. Then, the
lower frame body 29 rotates about the pin 29a provided at the front
end of its outer lateral surface 29c such that its rear end moves
vertically downward. As a result, the axis of rotation of the
mandrel 21 attached between the bridging frames of the movable
frame 22 is inclined such that a gap between a vertical upper
portion of the outer peripheral surface of the mandrel 21, and the
outer peripheral surface of the main roll 11 becomes smaller than a
gap between a vertical lower portion of the outer peripheral
surface of the mandrel, and the outer peripheral surface of the
main roll 11.
[0074] On the contrary, if the rod 32a of each elevating cylinder
32 is extended from this parallel state, as shown in FIG. 8, the
distance between the lower surface of the upper fitting projection
31a and the upper surface of the lower fitting projection 31b
becomes large. Then, as shown in FIG. 9, the lower frame body 29
rotates about the pin 29a provided at the front end of its outer
lateral surface 29c such that its rear end moves vertically upward.
As a result, the axis of rotation of the mandrel 21 attached to the
rotary frame 22 is inclined such that a gap between the vertical
lower portion of the outer peripheral surface of the mandrel 21,
and the outer peripheral surface of the main roll 11 becomes
smaller than a gap between the vertical upper portion of the outer
peripheral surface of the mandrel, and the outer peripheral surface
of the main roll 11.
[0075] As mentioned above, the mandrel 21 is supported so as to be
capable of being inclined with respect to the axis of rotation of
the main roll 11 such that the gap dimension between the outer
peripheral surface of the mandrel and the outer peripheral surface
of the main roll 11 differ on one side and the other side in the
direction of its axis of rotation.
[0076] A ring rolling method using the ring rolling mill 10 of this
embodiment will be described below.
[0077] First, the advance/retreat driving cylinder 27 is retreated
to separate the main roll 11 and the mandrel 21 from each other,
and to retreat the axial rolls 41 with respect to the ring-shaped
body W. In this state, after the opening/closing cylinder 26 is
extended to rotate the upper frame 23 vertically upward along with
the mandrel 21 about the pin 25a inserted through the intermediate
frame 25, the ring-shaped body W is arranged. Thereafter, the
opening/closing cylinder 26 is retracted to rotate the upper frame
23 vertically downward about the pin 25a along with the mandrel 21.
Then, the outer peripheral surface of the main roll 11 and the
outer peripheral surface of the ring-shaped body W are made to face
each other, and the outer peripheral surface of the mandrel 21 and
the inner peripheral surface of the ring-shaped body W are made to
face each other.
[0078] At this time, the pair of axial rolls 41 are advanced toward
the ring-shaped body W, and the ring-shaped body W is pinched in
its thickness direction by the outer peripheral surface of these
axial rolls 41. Also, the advance/retreat driving cylinder 27 is
extended to bringing the mandrel 21 close to the main roll 11. As a
result, the peripheral portion of the ring-shaped body W is pinched
in its radial direction between the outer peripheral surface of the
mandrel 21 and the outer peripheral surface of the main roll
11.
[0079] Next, the ring-shaped body W is rotated in its peripheral
direction by rotationally driving the main roll 11 and the axial
rolls 41 about each axis of rotation. Then, while the mandrel 21
rotates about its axis of rotation, the peripheral portion of the
ring-shaped body W is rolled in its radial direction over its whole
periphery. In this rolling process, as the thickness of the
peripheral portion of the ring-shaped body W in its radial
direction becomes smaller, the mandrel 21 gradually advances toward
the outer peripheral surface of the main roll 11 by the pressing
force to the fixed frame 12 by the advance/retreat driving cylinder
27. Moreover, in this rolling process, as the diameter of the
ring-shaped body W increases, the axial rolls 41 gradually retreats
radially outward of the ring-shaped body W.
[0080] In this rolling process, if necessary, each elevating
cylinder 32 is extended or retracted from its parallel state.
Thereby, the axis of rotation of the mandrel 21 is inclined with
respect to the axis of rotation of the main roll 11 such that the
gap between the outer peripheral surface of the mandrel and the
outer peripheral surface of the main roll 11 differs on one side
and the other side in the direction of its axis of rotation.
Thereby, the pressing force applied on the ring-shaped body W can
be changed along its axis direction.
[0081] In addition, the taper of the ring-shaped body W can also be
removed utilizing a rocking mechanism of the mandrel 21 in the ring
rolling mill 10. This will be described with reference to FIGS. 10A
to 10C. As shown in FIG. 10A, when any variation exists in the
material shape of the ring-shaped body W in a case where the
ring-shaped body can be normally rolled with constant thickness
along its axis, the ring-shaped body W may be tapered as shown in,
for example, FIG. 10B. In such a case, as shown in FIG. 10C, the
taper of the ring-shaped body W can be removed by performing
rolling while the mandrel 21 is inclined at a proper angle with
respect to the main roll 11.
[0082] As described above, in the ring rolling mill 10 of this
embodiment, a configuration in which the main roll 11 and the
mandrel 21 are provided so that they can be brought close to or
separated from each other, and the movable frame 22 (mandrel
inclining/supporting mechanism) which inclines and supports the
mandrel 21 with respect to the axis of rotation of the main roll 11
is provided such that the dimension of the gap between the outer
peripheral surface of the main roll 11 and the outer peripheral
surface of the mandrel 21 differs on vertical upper side (one side)
and on vertical lower side (other side) as seen in a direction
along the axis of rotation of the main roll 11 is adopted.
Moreover, a configuration in which the movable frame 22 includes
each upper frame 23 and each lower frame 24 (supporting frame)
which support upper and lower ends of the mandrel 21; and the
second fitting projection 31 (frame tilting mechanism) which tilts
the upper frame 23 and the lower frame 24 is adopted.
[0083] According to this configuration, the pressing forces applied
on the peripheral portion of the ring-shaped body W by the main
roll 11 and the mandrel 21 can be made different not only along
every peripheral position of the peripheral portion, but also along
positions in the thickness direction. As a result, the pressing
forces can be made different in every portion rolled in the
peripheral portion of the ring-shaped body W, that is, locally.
[0084] For example, while the ring-shaped body W makes one rotation
in the process during which the ring-shaped body W is rolled while
being rotated in its peripheral direction, the inclination angle of
the mandrel can be made different two or more times, or the mandrel
can be kept at the same inclination angle while the ring-shaped
body makes one rotation.
[0085] Further, since the mandrel 21 is inclinedly supported, when
the peripheral portion of the ring-shaped body W is rolled over the
whole area in its thickness direction, the mandrel 21 is inclined
such that the gap between the outer peripheral surface of the
mandrel and the outer peripheral surface of the main roll 11
becomes smaller on one side in the direction of its axis of
rotation than on the other side in the direction of its axis of
rotation. Thereby, the portion of the peripheral portion of the
ring-shaped body W which faces the portion of the outer peripheral
surface of the mandrel 21 on the other side in the direction of the
axis of rotation can be rolled over its whole periphery by
inclining the mandrel 21 such that the gap becomes smaller on the
other side in the direction of its axis of rotation than on one
side in the direction of its axis of rotation after the portion of
the peripheral portion of the ring-shaped body W which faces the
portion of the outer peripheral surface of the mandrel 21 on one
side in the direction of the axis of rotation.
[0086] Accordingly, when the whole area of the peripheral portion
of the ring-shaped body W in its thickness direction is rolled over
its whole periphery, this peripheral portion are rolled over its
whole periphery in twice half and half in its thickness direction.
Thereby, the contact area between the peripheral portion of the
ring-shaped body W and the mandrel 21 at every rolling is made
small, so that the compressive stress applied on the peripheral
portion of the ring-shaped body W can be increased. Thereby, the
amount of processing which rolls the peripheral portion of the
ring-shaped body W in the radial direction can be made large in a
state where the driving force which brings the main roll 11 and the
mandrel 21 close to each other are kept equal to that of an
existing model. Consequently, both an increase in the rolling
amount of the ring rolling mill 10 and the compactness thereof can
be made compatible with each other. Moreover, since the ring-shaped
body W can be rolled while being rotated in its peripheral
direction without being removed from the ring rolling mill 10, the
efficiency of processing can also be made high.
Second Embodiment
[0087] Subsequently, a second embodiment of the present invention
will be described below, referring to FIG. 11A to FIG. 15. In
addition, in the following description, differences from those of
the first embodiment will be mainly described, and the other points
are the same as those of the first embodiment, and the description
thereof will be omitted.
[0088] In the above first embodiment, the mandrel 21 is inclined by
rotating the whole movable frame 22 in the vertical direction,
whereas in the ring rolling mill 110 of this embodiment, the
mandrel 21 is inclined by horizontally translating a member
(hereinafter, upper frame 123) equivalent to the upper frame 23.
This embodiment is particularly different from the above first
embodiment in regard to this point.
[0089] As shown in FIG. 11A, a ring rolling mill 110 of this
embodiment includes a tilting frame 122 as the mandrel
inclining/supporting mechanism of the present invention.
[0090] The tilting frame 122 includes a pair of upper frames 123
which extend horizontally toward the main roll 11 from the mandrel
21, a pair of lower frames 124 which are provided vertically below
the upper frames 123 and extend substantially parallel to an
extension direction of the upper frames 123, and an intermediate
frame 125 which connects each upper frame 123 and each lower frame
124. The intermediate frame 125 connects the rear end of each upper
frame 123 and the rear end of each lower frame 124 opposite their
front ends on the side where the mandrel 21 is disposed.
[0091] In addition, in FIGS. 11A, 12, and 13, illustration of the
rail portions 28 is omitted for the purpose of explanation. This is
also the same in the following third to fifth embodiments.
[0092] Bridging frames (not shown) which connect the pair of upper
frames 123 and the pair of lower frames 124, respectively, are
disposed at the front end of each upper frame 123 and at the front
end of each lower frame 124, respectively. Both ends of the mandrel
21 in the direction of its axis of rotation are supported by these
bridging frames so as to be rotatable around the vertical axis of
the mandrel.
[0093] The bridging frame (first mandrel supporting portion)
between the lower frames 124 rotatably supports a lower end (one
end) of the mandrel 21 in place around a horizontal axis (that is,
an axis vertical to the sheet plane of FIG. 11A) in a position
which intersects the axis of rotation of the mandrel 21 and is
twisted with respect to the axis of rotation of main roll 11.
Further, the bridging frame (second mandrel supporting portion)
between the upper frames 123 rotatably supports an upper end (other
end) of the mandrel 21 around the horizontal axis (that is, an axis
vertical to the sheet plane of FIG. 11A) in a position which
intersects the axis of rotation of the mandrel 21 and is twisted
with respect to the axis of rotation of the main roll 11.
[0094] The supporting structure of the mandrel 21 will be described
in detail, referring to FIGS. 14 and 15.
[0095] The bridging frame between the lower frames 124 is provided
with a fixed portion 150 which is integrally attached to this
bridging frame, a horizontal shaft 151 fixed to the fixed portion
150, and a rotary portion 153 which is attached to the horizontal
shaft 151 so as to be rotatable about a horizontal axis CL1.
[0096] The fixed portion 150 includes a bottom wall 150a, and a
pair of side walls 150b formed vertically upward from both ends of
the bottom wall 150a. A through hole 150b1 for allowing the
horizontal shaft 151 to be inserted therethrough is formed along
the horizontal direction in each side wall 150b. Further, as shown
in FIG. 15, the upper surface of the bottom wall 150a defines a
circular-arc surface 150a1 as seen in a cross-section vertical to
the horizontal axis CL1.
[0097] The rotary portion 153 is arranged between the side walls
150b, and includes a rotary portion main body 153a in which a
through hole 151a through which the horizontal shaft 151 is
inserted along the horizontal direction, and a thrust bearing 153b
and an axial bearing 153c which are provided inside an opening
formed at an upper end of the rotary portion main body 153a. The
thrust bearing 153b supports the thrust load by the mandrel 21, and
the axial bearing 153c supports the bending load which acts on the
mandrel 21. A lower end of the mandrel 21 is rotatably supported
about the axis of the mandrel by the thrust bearing 153b and the
axial bearing 153c.
[0098] As shown in FIG. 15, as seen in the cross-section vertical
to the horizontal axis CL1, a lower surface of the rotary portion
main body 153a defines a circular-arc surface 153a1 which forms a
fixed gap with respect to the circular-arc surface 150a1, and
interferes with the fixed portion 150 during the rotation of the
rotary portion main body 153a. Accordingly, the thrust load and
bending load of the mandrel 21 are transmitted to the thrust
bearing 153b and axial bearing 153c, the rotary portion main body
153a, the horizontal shaft 151, each side wall 150b, and the
bridging frame between the lower frames 124.
[0099] Further, the bridging frame between the upper frames 123 is
provided with a fixed portion 160 which is integrally attached to
this bridging frame, a horizontal shaft 161 fixed to the fixed
portion 160, and a rotary portion 163 which is attached to the
horizontal shaft 161 so as to be rotatable about a horizontal axis
CL2.
[0100] The fixed portion 160 includes a top wall 160a, and a pair
of side walls 160b formed vertically downward from both ends of the
top wall 160a. A through hole 160b1 for allowing the horizontal
shaft 161 to be inserted therethrough is formed along the
horizontal direction in each side wall 160b. Further, as shown in
FIG. 15, the lower surface of the top wall 160a defines a
circular-arc surface 160a1 as seen in a cross-section vertical to
the horizontal axis CL.
[0101] The rotary portion 163 is arranged between the side walls
160b, and includes a rotary portion main body 163a in which a
through hole 161a through which the horizontal shaft 161 is
inserted along the horizontal direction, and a thrust bearing 163c
which is provided inside an opening formed at a lower end of the
rotary portion main body 163a. The axial bearing 163c supports the
bending load which acts on the mandrel 21. An upper end of the
mandrel 21 is rotatably supported about the axis of the mandrel by
the axial bearing 163c.
[0102] As shown in FIG. 15, as seen in the cross-section vertical
to the horizontal axis CL2, an upper surface of the rotary portion
main body 163a defines a circular-arc surface 163a1 which forms a
fixed gap with respect to the circular-arc surface 160a1, and
interferes with the fixed portion 160 during the rotation of the
rotary portion main body 163a. Accordingly, the bending load of the
mandrel 21 is transmitted to the axial bearing 163c, the rotary
portion main body 163a, the horizontal shaft 161, each side wall
160b, and the bridging frame between the lower frames 123.
[0103] Also, the fixed portion 150 which supports the lower end of
the mandrel 21 is fixed in place along with the bridging frame
arranged between the lower frames 124, while the fixed portion 160
which supports the upper end of the mandrel 21 moves in the
horizontal direction along with the bridging frame arranged between
the upper frames 123. Thus, as shown by arrows of FIG. 15, the
mandrel 21 can be rocked so as to be brought close to or separated
from the main roll 11 while the mandrel is kept rotatable around
its axis of rotation.
[0104] As shown in FIGS. 11A and 11B, the ring rolling mill 110 of
this embodiment is equipped with a driving section 170 (first
mandrel driving section) which brings or separates the bridging
frame (second mandrel supporting portion) between the upper frames
123 close to or from the main roll 11.
[0105] This driving section 170 includes an eccentric shaft 171
which is laid between the intermediate frames 125 in place on each
lower frame 124 and has a horizontal axis CL3 extending parallel to
the horizontal axes CL1 and CL2; the upper frame 123 (first
connecting frame) which connects the eccentric shaft 171, and the
bridging frame between the upper frames 123; and a rotation driving
portion (not shown) which rotates the eccentric shaft 171 around
the horizontal axis CL3.
[0106] Pins 172 which are parallel to the horizontal axis CL3 and
are provided in positions which are made eccentric by eccentricity
d are respectively provided at both ends of the eccentric shaft
171.
[0107] A ring rolling method using the ring rolling mill 110 of
this embodiment having the configuration described above will be
described below.
[0108] First, in a case where rolling is performed with a stronger
pressing force at the lower end of the peripheral portion of the
ring-shaped body W than at the upper end thereof, the rotation
driving portion is started to rotate the eccentric shaft 171 in one
direction. Then, as shown in FIG. 12, each upper frame 123 slides
to the right in the figure. Therefore, the bridging frame laid
between the upper frames 123 also moves to the right in the figure.
As a result, the upper end of the mandrel 21 also moves to the
right in the figure. By stopping the rotation driving portion in a
state where the mandrel 21 is inclined at a desired angle in this
way, as shown in FIG. 12, the mandrel 21 can be inclined and
supported with respect to the axis of rotation of the main roll 11
such that the gap between the outer peripheral surface of the
mandrel 21 and the outer peripheral surface of the main roll 11
becomes narrower on the lower side (the other side) than on the
upper side (one side) as seen in a direction along the axis of
rotation of the main roll 11.
[0109] Further in a case where rolling is performed with a stronger
pressing force at the upper end of the peripheral portion of the
ring-shaped body W than at the lower end thereof, the rotation
driving portion is started to rotate the eccentric shaft 171 in the
reverse direction. Then, as shown in FIG. 13, each upper frame 123
slides to the left in the figure. Therefore, the bridging frame
laid between the upper frames 123 also moves to the left in the
figure. As a result, the upper end of the mandrel 21 also moves to
the left in the figure. By stopping the rotation driving portion in
a state where the mandrel 21 is inclined at a desired angle in this
way, as shown in FIG. 13, the mandrel 21 can be inclined and
supported with respect to the axis of rotation of the main roll 11
such that the gap between the outer peripheral surface of the
mandrel 21 and the outer peripheral surface of the main roll 11
becomes narrower on the upper side (the other side) than on the
lower side (one side) as seen in a direction along the axis of
rotation of the main roll 11.
[0110] In addition, the operation in which the mandrel 21 is
brought close to or separated from the main roll 11 in a state
where the inclining of the mandrel 21 is fixed can be performed by
driving to advance/retreat the advance/retreat driving cylinder 27,
and horizontally moving the whole tilting frame 122 to the right
and left in the figure.
[0111] As described above, according to the ring rolling mill 110
of this embodiment, the same operational effects as those of the
ring rolling mill 10 of the above first embodiment can be obtained.
That is, according to the ring rolling mill 110 of this embodiment,
the pressing forces applied on the peripheral portion of the
ring-shaped body W by the main roll 11 and the mandrel 21 can be
made different not only along every peripheral position of the
peripheral portion, but along positions in the thickness
direction.
Third Embodiment
[0112] Subsequently, a third embodiment of the invention will be
described below, referring to FIGS. 16 to 18. In addition, in the
following description, differences from those of the second
embodiment will be mainly described, and the other points are the
same as those of the second embodiment, and the description thereof
will be omitted.
[0113] In the above second embodiment, each upper frame 123 is made
to slide by the rotation of the eccentric shaft 171, whereas in the
ring rolling mill 210 of this embodiment, the mandrel 21 is tilted
by horizontally expanding and retracting a member (hereinafter,
upper frame 223) equivalent to the upper frame 123. This embodiment
is particularly different from the above second embodiment in
regard to this point.
[0114] As shown in FIG. 16, the ring rolling mill 210 of this
embodiment includes a pair of intermediate frames 225 which form
base portions fixed in place on the lower frames 124, respectively;
a shaft body 271 which is laid between the intermediate frames 225,
and has a horizontal axis CL5 parallel to the horizontal axes CL1
and CL2; a pair of upper frames 223 which are rotatably connected
to the shaft body 271, and extend horizontally toward the main roll
11 from the mandrel 21.
[0115] Each upper frame 223 includes a fixed-side frame 223a which
is rotatably attached to the shaft body 271; a sliding-side frame
223b which is attached to a tip of the fixed-side frame 223a so as
to be movable in the horizontal direction; and a sliding driving
portion 270 which brings or separates the sliding-side frame 223b
close to or from the fixed-side frame 223a along the horizontal
direction.
[0116] Between front ends of the sliding-side frames 223b, a
bridging frame (not shown) which connects the front ends is
disposed. The front end of the mandrel 21 in the direction of its
axis of rotation is supported by this bridging frame so as to be
rotatable around the vertical axis of the mandrel. In addition, in
this embodiment, each fixed-side frame 223a constitutes the base
portion of the invention, and the sliding frame 223b constitutes a
second connecting frame of the invention.
[0117] A ring rolling method using the ring rolling mill 210 of
this embodiment having the configuration described above will be
described below.
[0118] First, in a case where rolling is performed with a stronger
pressing force at the lower end of the peripheral portion of the
ring-shaped body W than at the upper end thereof, each sliding-side
frame 223b is made to slide to the right in the figure by extending
the sliding driving portion 270. Then, the bridging frame laid
between the sliding-side frames 223b also moves to the right in the
figure. As a result, the upper end of the mandrel 21 also moves to
the right in the figure. By stopping the sliding driving portion
270 in a state where the mandrel 21 is inclined at a desired angle
in this way, as shown in FIG. 17, the mandrel 21 can be inclined
and supported with respect to the axis of rotation of the main roll
11 such that the gap between the outer peripheral surface of the
mandrel 21 and the outer peripheral surface of the main roll 11
becomes narrower on the lower side (the other side) than on the
upper side (one side) as seen in a direction along the axis of
rotation of the main roll 11.
[0119] Further, in a case where rolling is performed with a
stronger pressing force at the upper end of the peripheral portion
of the ring-shaped body W than at the lower end thereof, each
sliding-side frame 223b is made to slide to the left in the figure
by retracting the sliding driving portion 270. Then, the bridging
frame laid between the sliding-side frames 223b also moves to the
left in the figure. As a result, the upper end of the mandrel 21
also moves to the left in the figure. By stopping the sliding
driving portion 270 in a state where the mandrel 21 is inclined at
a desired angle in this way, as shown in FIG. 18, the mandrel 21
can be inclined and supported with respect to the axis of rotation
of the main roll 11 such that the gap between the outer peripheral
surface of the mandrel 21 and the outer peripheral surface of the
main roll 11 becomes narrower on the upper side (the other side)
than on the lower side (one side) as seen in a direction along the
axis of rotation of the main roll 11.
[0120] In addition, the operation in which the mandrel 21 is
brought close to or separated from the main roll 11 in a state
where the inclining of the mandrel 21 is fixed can be performed by
driving to advance/retreat the advance/retreat driving cylinder 27,
and horizontally moving the whole tilting frame 122 to the right
and left in the figure.
[0121] As described above, according to the ring rolling mill 210
of this embodiment, the same operational effects as those of the
ring rolling mill 110 of the above second embodiment can be
obtained. That is, according to the ring rolling mill 210 of this
embodiment, the pressing forces applied on the peripheral portion
of the ring-shaped body W by the main roll 11 and the mandrel 21
can be made different not only along every peripheral position of
the peripheral portion, but also along positions in the thickness
direction.
Fourth Embodiment
[0122] Subsequently, a fourth embodiment of the invention will be
described below, referring to FIGS. 19 to 21. In addition, in the
following description, differences from those of the second
embodiment will be mainly described, and the other points are the
same as those of the second embodiment, and the description thereof
is omitted.
[0123] In the above second embodiment, a portion on the side of the
mandrel 21 is rocked, whereas in a ring rolling mill 310 of this
embodiment, a portion on the side of the main roll 11 is rocked.
This embodiment is particularly different from the above second
embodiment in regard to this point.
[0124] As shown in FIG. 19, the ring rolling mill 310 of this
embodiment includes a main roll inclining/supporting mechanism
which inclines and supports the main roll 11 with respect to the
axis of rotation of the mandrel 21 such that the gap between the
outer peripheral surface of the mandrel 21 and the outer peripheral
surface of the main roll 11 differs on vertical upper side (one
side) and on vertical lower side (other side) as seen in a
direction along the axis of rotation of the mandrel 21.
[0125] This main roll inclining/supporting mechanism includes a
spherical bearing 320 (first main roll supporting portion) which
rotatably supports the lower end (one end) of the main roll 11 in
place, an upper bearing 330 (second main roll supporting portion)
which rotatably supports the upper end (other end) of the main roll
11, and a main roll driving portion 340 (first main roll driving
portion) which brings or separates the upper bearing 330 close to
or from the mandrel 21.
[0126] Further, the ring rolling mill 310 of this embodiment
further includes a main roll driving source 350 which generates a
driving force which rotates the main roll 11, a transmission
section 360 which transmits a rotational driving force from the
main roll driving source 350 to the main roll 11, and a pedestal
370 on which the main roll driving source 350 and the transmission
section 360 are installed. The transmission section 360 is provided
with a gear mechanism 361 for transmitting a rotational driving
force from the main roll driving source 350, and the spherical
bearing 320 which supports the lower end of the main roll 11 so
that the main roll 11 can be rocked in a direction in which it is
brought close to or separated from the mandrel 21. The gear
mechanism 361 and the lower end of the main roll 11 are connected
together via bevel gears 362 and 363, and the rotational driving
force from the main roll driving source 350 is transmitted to the
gear mechanism 361, the bevel gears 362 and 363, and the main roll
11. Even if the main roll 11 rocks during transmission of this
rotational driving force, a bending joint (not shown) is provided
in the gear mechanism 361 so that the engagement between the bevel
gears 362 and 363 may be maintained suitably.
[0127] The main roll driving portion 340 is a hydraulic cylinder
provided between the fixed frame 12 and the upper bearing 330, and
brings or separates the main roll 11 close to or from the fixed
frame 12 as the driving portion itself performs
extension/retraction operation. As mentioned above, since the lower
end of the main roll 11 is rockably supported on the spherical
bearing 320, the main roll 11 can be tilted around a horizontal
axis CL6 vertical to the sheet plane so that it can be brought
close to or separated from the mandrel 21 fixed in place by driving
the main roll driving portion 340. The horizontal axis CL6 is in a
position which intersects the axis of the main roll 11, and is
twisted with respect to the axis of the mandrel 21.
[0128] A ring rolling method using the ring rolling mill 310 of
this embodiment having the configuration described above will be
described below.
[0129] First, in a case where rolling is performed with a stronger
pressing force at the upper end of the peripheral portion of the
ring-shaped body W than at the lower end thereof, the main roll 11
is tilted to the right in the figure about the horizontal axis CL6
by driving the main roll driving portion 340 to extend it. By
stopping the main roll driving portion 340 in a state where the
main roll 11 is inclined at a desired angle in this way, as shown
in FIG. 20, the mandrel 21 can be inclined and supported with
respect to the axis of rotation of the main roll 11 such that the
gap between the outer peripheral surface of the mandrel 21 and the
outer peripheral surface of the main roll 11 becomes narrower on
the upper side (the other side) than on the lower side (one side)
as seen in a direction along the axis of rotation of the main roll
11.
[0130] Further, in a case where rolling is performed with a
stronger pressing force at the lower end of the peripheral portion
of the ring-shaped body W than at the upper end thereof, the main
roll 11 is tilted to the left in the figure about the horizontal
axis CL6 by driving the main roll driving portion 340 to retract
it. By stopping the main roll driving portion 340 in a state where
the main roll 11 is inclined at a desired angle in this way, as
shown in FIG. 21, the mandrel 21 can be inclined and supported with
respect to the axis of rotation of the main roll 11 such that the
gap between the outer peripheral surface of the mandrel 21 and the
outer peripheral surface of the main roll 11 becomes narrower on
the lower side (the other side) than on the upper side (one side)
as seen in a direction along the axis of rotation of the main roll
11.
[0131] In addition, the operation in which the mandrel 21 is
brought close to or separated from the main roll 11 in a state
where the inclining of the main roll 11 is fixed can be performed
by driving to advance/retreat the advance/retreat driving cylinder
27, and horizontally moving the whole supporting structure of the
mandrel 21 to the right and left in the figure.
[0132] As described above, according to the ring rolling mill 310
of this embodiment, the same operational effects as those of the
ring rolling mill 110 of the above second embodiment can be
obtained. That is, according to the ring rolling mill 310 of this
embodiment, the pressing forces applied on the peripheral portion
of the ring-shaped body W by the main roll 11 and the mandrel 21
can be made different not only along every peripheral position of
the peripheral portion, but also along every position in the
thickness direction.
Fifth Embodiment
[0133] Subsequently, a fifth embodiment of the invention will be
described below, referring to FIGS. 22 to 24. In addition, in the
following description, differences from those of the fourth
embodiment will be mainly described, and the other points are the
same as those of the fourth embodiment, and the description thereof
is omitted.
[0134] In the above fourth embodiment, a portion on the upper end
of the main roll 11 is rocked, whereas in a ring rolling mill 410
of this embodiment, a portion on the lower end of the main roll 11
is rocked. This embodiment is particularly different from the above
fourth embodiment in regard to this point.
[0135] As shown in FIG. 22, the ring rolling mill 410 of this
embodiment includes a main roll inclining/supporting mechanism
which inclines and supports the main roll 11 with respect to the
axis of rotation of the mandrel 21 such that the gap between the
outer peripheral surface of the mandrel 21 and the outer peripheral
surface of the main roll 11 differs on vertical upper side (one
side) and on vertical lower side (other side) as seen in a
direction along the axis of rotation of the mandrel 21.
[0136] This main roll inclining/supporting mechanism includes a
supporting pin 420 (first main roll supporting portion) which
rotatably supports the upper end (one end) of the main roll 11 in
place, a spherical bearing 430 (second main roll supporting
portion) which rotatably supports the lower end (other end) of the
main roll 11, and a main roll driving portion 440 (first main roll
driving portion) which brings or separates the spherical bearing
430 close to or from the mandrel 21.
[0137] The supporting pin 420 supports the upper end of the main
roll 11 so that it can be tilted around a horizontal axis CL7 (axis
vertical to the sheet plane of FIG. 22) which intersects the axis
of the main roll 11 and is twisted with respect to the axis of the
mandrel 21.
[0138] The pedestal 370 of this embodiment is provided with wheels
371 which support the pedestal 370 so as to be able to run along
one direction. Accordingly, the main roll driving source 350 and
the transmission section 360 are integrated with the pedestal 370,
and move to the right and left in FIG. 22.
[0139] The main roll driving portion 440 includes an anchor 441
which is installed in place, and a hydraulic cylinder 442 which is
provided between the anchor 441 and the main roll driving source
350. When the hydraulic cylinder 442 performs extension/retraction
operation, the main roll driving portion moves the main roll
driving source 350, the transmission section 360, and the pedestal
370 to the right and left in FIG. 22. As mentioned above, since the
upper end of the main roll 11 is rockably supported by the
supporting pin 420, the main roll 11 can be tilted around the
horizontal axis CL7 so that it can be brought close to or separated
from the mandrel 21 fixed in place by driving the main roll driving
portion 440.
[0140] A ring rolling method using the ring rolling mill 410 of
this embodiment having the configuration described above will be
described below.
[0141] First, in a case where rolling is performed with a stronger
pressing force at the lower end of the peripheral portion of the
ring-shaped body W than at the upper end thereof, the main roll 11
is tilted to the right in the figure about the horizontal axis CL7
by driving the main roll driving portion 440 to extend the
hydraulic cylinder 442. By stopping the main roll driving portion
440 in a state where the main roll 11 is inclined at a desired
angle in this way, as shown in FIG. 23, the mandrel 21 can be
inclined and supported with respect to the axis of rotation of the
main roll 11 such that the gap between the outer peripheral surface
of the mandrel 21 and the outer peripheral surface of the main roll
11 becomes narrower on the lower side (the other side) than on the
upper side (one side) as seen in a direction along the axis of
rotation of the main roll 11.
[0142] Further, in a case where rolling is performed with a
stronger pressing force at the upper end of the peripheral portion
of the ring-shaped body W than at the lower end thereof, the main
roll 11 is tilted to the left in the figure about the horizontal
axis CL7 by driving the main roll driving portion 440 to retract
the hydraulic cylinder 442. By stopping the main roll driving
portion 440 in a state where the main roll 11 is inclined at a
desired angle in this way, as shown in FIG. 24, the mandrel 21 can
be inclined and supported with respect to the axis of rotation of
the main roll 11 such that the gap between the outer peripheral
surface of the mandrel 21 and the outer peripheral surface of the
main roll 11 becomes narrower on the upper side (the other side)
than on the lower side (one side) as seen in a direction along the
axis of rotation of the main roll 11.
[0143] In addition, the operation in which the mandrel 21 is
brought close to or separated from the main roll 11 in a state
where the inclining of the main roll 11 is fixed can be performed
by driving to advance/retreat the advance/retreat driving cylinder
27, and horizontally moving the whole supporting structure of the
mandrel 21 to the right and left in the figure.
[0144] As described above, according to the ring rolling mill 410
of this embodiment, the same operational effects as those of the
ring rolling mill 310 of the above fourth embodiment can be
obtained. That is, according to the ring rolling mill 410 of this
embodiment, the pressing forces applied on the peripheral portion
of the ring-shaped body W by the main roll 11 and the mandrel 21
can be made different not only along every peripheral position of
the peripheral portion, but along every position in the thickness
direction.
[0145] In addition, various shapes or combinations of respective
constituent members illustrated in the embodiments described above
are merely examples, and various changes may be made depending on
design requirements without departing from the spirit or scope of
the present invention.
[0146] For example, the configuration in which the axial rolls 41
are supported so that they can be rotationally driven around their
axes of rotation is shown in the above first embodiment. Instead of
this, however, the axial rolls 41 may be rotatably supported, and
may rotate as the ring-shaped body W is rotated in its peripheral
direction by the main roll 11 and the mandrel 21.
[0147] Further, in the first to fifth embodiments, either the
mandrel 21 or the main roll 11 is tilted to the other one. However,
the invention is not limited thereto. Both the mandrel 21 and the
main roll 11 may be tilted.
[0148] Further, in the second and third embodiments, only the upper
end supporting portion of the mandrel 21 is rocked. However, the
invention is not limited thereto. A drive mechanism (second mandrel
driving portion) which independently brings or separates both an
upper end supporting portion (third mandrel supporting portion) and
a lower end supporting portion (fourth mandrel supporting portion)
of the mandrel 21 close to or from the main roll 11.
[0149] Further, in the fourth and fifth embodiments, only either an
upper end supporting portion or a lower end supporting portion of
the main roll 11 is rocked. However, the invention is not limited
thereto. A drive mechanism (second main roll driving portion) which
independently brings or separates both the upper end supporting
portion (first main roll supporting portion) and the lower end
supporting portion (second main roll supporting portion) of the
main roll 11 close to or from the mandrel 21.
INDUSTRIAL APPLICABILITY
[0150] The pressing forces applied on the peripheral portion of the
ring-shaped body by the main roll and the mandrel can be made
different locally in the peripheral portion of the ring-shaped
body.
* * * * *